In the 2011 census Office for National Statistics, the proportion of Muslims in London had risen to 12.4% of the population (40% of England's Muslims). In Newham and Tower Hamlets, the percentages of Muslims were over 30%.

The first Muslims to settle in London were Bengali and Yemeni sailors from the 19th century. Many Muslims from the Commonwealth served in the British Army and British Indian Army in the First and Second World Wars. In the wave of immigration that followed the Second World War, many Muslims emigrated to the UK from these Commonwealth countries and former colonies. Initially, many came from Pakistan especially the Pakistani Punjab and Kashmir and the Indian state of Gujarat. This initial wave of immigration of the 1950s and 60s was followed by migrants from Cyprus, Sylhet Bangladesh, formerly East Pakistan. Many Muslims also arrived from various other countries, although the percentage is far smaller than from the Indian sub-continent. Amongst those from other countries, Muslims from Yemen, Somalia and Turkey have significant numbers, whereas those from Malaysia, Nigeria, Ghana and Kenya represent smaller fractions. Today, London's Muslims come from all over the world and there is a small but growing group of converts.

Proportion stating they were Muslim in the 2011 census in Greater London.

Most of London's Muslims are descendants of immigrants from the Indian subcontinent, particularly Pakistan, Bangladesh and India. There is also a large number of Muslims from Arab countries. Among African Muslims there are large Maghreb (including Algerian and Egyptian) communities and Somali communities, as well as the equally large 200,000 members of the West African Muslim community. In addition, London is home to large Turkish and Bosnian Muslim communities, both of which comprise over 30,000 members. The city also has a high number of restaurants that serve halal food (around 2,300).

However, this influx of immigrants has led to community relations issues. In the East End of London, there is a lot of tension in the area around East Ham, Barking and Dagenham between Muslims and non-Muslims. The British National Party gained their highest vote by proportion, 16.9%, in the 2005 General Election in Barking[2] and has 12 councillors on Barking & Dagenham Borough Council.[3]